The Praktiflex FX was a 35mm film single lens reflex camera made in Dresden East Germany region in the early 1950's for the export market.
The mirror is not self-returning, it is set when you wind to the next frame.
It features a waist level focusing screen with retractable magnifier, sockets on the front for F and X type flash synchronization, and 42mm threaded lens mount (Pentax/Praktika Universal Screw Mount) that will accept a huge number of lenses from many manufacturers. There is no exposure meter.
Stark in its design, the camera is solid and potentially capable.

I brought this camera home from the Belleville Illinois Flea Market. It cleaned up well, no corrosion, shutter curtains in excellent condition, and the leatherette was intact.
The high speeds all tested remarkably close to correct with electronic testing. But the low speed range does not function, the internal gear escapement is apparently not working.

I mounted a Russian made Helios-44 model f2/58mm lens and loaded it up with a roll of Kodak 200 film, then took it for a spin.
First and last images were at home, this year's tomato crop, not perfect due to drought and extreme heat, but tasty.
The rest of the set was shot at Laumeier Sculpture Park.
The fiberglass deer stands about 10 feet tall at the shoulders, and is a bit unsettling in appearance.

I did not include several images because they came out soft, due to mirror slap, or difficulties adjusting to the waist level focusing system, or qualities of the lens formulation. But there were plenty of sharp ones to make up for it.
The Kodak 200 film showed a lot of grain and dense color. That plus eccentricities of the Russian lens gave the set a different sort of flavor.

Please click on thumbnails to see enlarged.
All images are ©2018 E.J.Kowalski.
Thanks! Ed